Pair-heating-furnace hearth.



"1,034,858. Patented Aug. 6, 1912.

3 SHEBTRBHEET 2.'

Fig.6

INVENTOR T/Iomas V. A I i5 WITNESSES TUV. ALLIS. v PAIR HEATING FURNACEHEARTH. APPLICATION FILED SEPT.21,'1908. RENEWED NOV. 21. 1910.

3 SHEETS-SHEET 3.

WI TNESSES //VVEN7'0R TAO/has V 14/015 A TTOR/VEY Patented Aug. 6, 1912.

for the reason that cold bars may UNITED STATE PATENT OFFICE.

THOMAS V. ALLIS, OF BRIDGEPORT, CONNECTICUT.

PAIR-HEATING-FURNACE HEARTH.

To all whom it may concern' Be it known that I, THOMAS V. ALLIs, a

citizen. of the United States, residing at- Bridgeport, in ,the countyof Fairfield and State of Connecticut, have invented certain new anduseful Improvements in Pair- Heating-Furnace Hearths; and. I do herebydeclare the following to be a full, clear, a'nd'exact description of theinvention,such as will enable others skilled in the art to which itappertainsto make and use the same.

' My invention relates to pair heating furnaces and it consists of animproved hearth designed to be .-used in the heating chamber of suchfurnaces to uphold sheet bars laced thereon. supporting them upon one oitheir sides and'a lower longitudinal edge in a position inclinedlaterally to the perpendicular, thereby economizing space and increasingthe heating capacity of such chamber, and when: employed in-continuously heating such bars, it enables them to be forced alon thehearth in parallel rows. The bene ts derived from the use of my improvedhearthinthe ordinary pair heating chamber of the present sheet millfurnace consist: First-,*"m the ability to charge a greater number ofsaid bars therein all more advantageously located than now possible,thereby giving them the necessary time to become mellowed by the mildsoaking heat required for that purpose. Second, byheating the barsslowly they are brought to the proper rolling temperature withoutraising damaging scale upon their surface. Third, more continuousworking is possible soon be charged after the hot bars are taken out, sothat, by the time the hot bars have been progressively withdrawn alongthe hearth,

those at the opposite end from which the 'not bars were last drawn arein condition 1.0 roll, thus a system of rotative heating is established.Fourth, more bars are heated per unit of fuel consumed, from the factthat the hearth constantly receives and discharges the bars uniformly.Fifth, the work of the heater is less laborious as he -is not, under allconditions, obliged to ma nipulate and pile the bars Within the chamher.All of the above described benefits Specification of Letters Patent.

Patented Aug. 6, 1912.

:A ppliea'tion filed September 21,1908, Serial No. 453,977.ltenewed'November 21, 1910. Serial No. 593,545.

accrue alike in the use of my herein described improved .hearth inheating sheet bars in a continuous manner.

Figure 1 of the accompanying drawings s a. horizontal section of a gasfired continuous heating furnace taken on line a, a of Fig. 2 and showsin plan, collections of sheet bars cut to length with theirends crossedin reverse angular abutment and upheld upon my improved hearth withinthe heating chamber of said furnace. Fig. 2 is a transverse Verticalsection on line b, b of Fig. 1. Fig. 3 is a section broken from saidhearth through its base and the center of a portion of its verticalprojections, with sheet bars standing in the grooves thereon formed bysaid projections and in reverse angular abutment; two of the collectionsof bars are shown in cross section, and portions of two in endelevation, all enlarged. Fig. 4 is an enlarged plan view of my improvedcast steel hearth shown in Figs. 1 and 2: the base has integrallyconnected individual projections disposed over its top surface, whichform a series of parallel grooves suitable to uphold therein sheet barsin angular position. Fig. 5 is a transverse vertical section on line 0,c of Fig. 4., Fig. 6 is a plan view in longitudinal section on line (1,(Z of Fig. 7 and shows the improved hearth constructed of burnedfireclay or other refractory material and located'in the heating chamberof an ordinary pair heating furnace, the fire box and bridge wall commonto such furnaces beingshown. Fig. 7 is a vertical longitudinal sectionon line 6, e of Fig. 6. Fig. 8 is a plan view in longitudinal section on.line f, f of Fig. 9 and shows collections of sheet bars all upheld atone inclination upon said hearth with their adjacent ends separated.Fig. 9 is a vertical longitudinal scctiomon line g, g of Fig. 8. Figs.10, 1-1 and 12 are sections of varied forms of the hearth which may beconstructed of metal or refractory material. Fig. 10, likeFig.,3,,.shows sheet bars upheld upon the hearth in reverse angularposition having their ends twice crossed but supported more obliquely. F1g. 11', also like Fig. 3, shows sheet bars upheld upon t'he hearth in.reverse angular position. but unlike Fig. 3, their ends are but oncecrossed and the bars are supported at a more acute angle. Fig. 12, likeFig. 9, shows sheet bars upheld at one and the same inclination to theerpendicular, the bars of Fig. 12, however, eing supported at a moreobhque angle by grooves and projections of saw tooth shape.

are sheet bars. 11 the improved .hearth of varied shapes. 12 one of a se10 ries of parallel upholding grooves in said hearth formed by parallelvertical projections. 13 the parallel vertical .projections which formsaid grooves and constitute a part of the hearth. 14 the lateral angular5 bar supporting base of said projections and 15 the upper barsupporting portion. 16 that portion of the projections of the hearth(see Figs. 3 and 11)'which is uncovered by sheet .bars while in heated.17 of Fig. 1, a shelf at the charging end of the heating chamber. 18 ofFigs. 6 and 8 the side of the heating chamber of an ordinarypair heatingfurnace in which the charging and discharging doors are located. Theyconsist of a series of comparatively small doors that raise verticallyand overlap each other at their sides,

so that, while the large opening will be en- 7 tirely closed when thedoors are all down, all parts of the hearth are madeaccessible throughsaid doors. Doors not shown in thedrawings. 19 the chargin end of thecontinuous heating chamber 0% Fig. 1 and 20 its discharging end.

The upholding hearth embodies two well known axioms, First, that acollection of rectangular shapes of given dimensions standing uprightupon one of their longitudinal edges with their" sides in contact, 40occupy less transverse space than the same number of such shapes lyingfiat-wise with their longitudinal edges in contact, and while I do notplace sheet bars upon my hearth in the first position'above described,

I do in a modified way, upholding them upon their lower longitudinal,edge and one of their sides at a greater or less inclination to theperpendicular.

The second axiom availed of is, that two rectangular pieces of solidmaterial having their abutting-ends crossed, can not be forced past eachother or one over the other and that the power applied to move one piecemoves its contacting neighbor in the same sustained line and direction;1 To utilize the above described axioms, I construct my improved hearthwith a series of parallel grooves formed by a series of parallelprojections, which together torm a hearth having suitable grooves touphold sheet bars placed longitudinally therein in a position inclinedlaterally to the perpen- 'dicularand in conformity to the second "axiom,the groovesbear such transverse refifrlation to each other that whenlongitudithe process of being.

hearth nal rows of said bars are consecutively placed alternately, anglewithin the prgjections, they-will cross at their adjacent en s.

Fig. 3 shows bars in collections standing reversed. and atan angle of45; however,

in sections, at a reverse grooves formed by said as the degrees oflateral inclination to the.

perpendicular are immaterial to my inventhe side of an angle extendingfrom said lateral base 14 to said outer portion 15 as great as theentire width of the bars, if

desired, when the bars are not to cross at their ends-above theprojections.

One of the important benefits inherent-to the use of my improved hearthis the following: Although the hearth of a heating chamber contains morebars per square foot when supported thereon at an angle of 45 orthereabouts, than can be placedin the same space when laid flatwise withedges and ends in contact, I still secure upon the a large area ofuncovered space 16, Fig. 3. This uncovered space is exposed to thenormal. heat of the furnace which it absorbs, so that, when sheet barsare being heated in a continuous manner with their ends crossed inreverse angular abutment, each collection of bars is brought over thefreshly heated supports which have been exposed to thesame heat and forthe same length of time as the bars. Hence, all of the. collections ofbars at each of their advanced steps-are brought. over the uncoveredheated spaces which are of the same general caloric condition as thefurnace, which not only prevents the under side of the bars tron.becoming chilled, but is a means of augmenting their temperature. Thesame advantages accrue to the use of my hearth when placed in anyordinary pair heating furnace, where, instead of arranging the rows ofbars singlycr in collection alternately at a reverse angle, the rows,may, if preferred, all be placed at the same angle and in one direction,as shown at Figs. 8 and 9, there being no danger of the bars overridingeach other as there is no impelling force brought against their ends,each collection being ma nipulated separately. In event of the bars allstanding at the same angle and direction as shown in Figs. 8 and 9; itis obvious that the opposite surfaces of the supporting projectionsbeing largely uncovered by bars,

than one-half the against them and at a reverse angle to the precedingcharge, the bars rest upon hot supports, so that, by alternating theposition of each charge, the bars all have hot supports to rest against.

Vhile the hearth of Fig. 12 does not possess the foregoing describedcharacteristics of the hearths of Figs. 3, 9 and 11 for recuperatingheat in the portion 16 of the equiangular projections 13 of thosefigures; the grooves 12 ofFig. 12 are closer together than grooves 12 ofFigs. 3, 9 and 10and 11, which gives the hearth of Fig. 12 greater barupholding capacity per square foot than the hearths of said figures, thesame' number of bars being placed in respective grooves.

In operating my improved hearth in the heating chambtu' of an ordinarypair heating furnace, (see Figs. 6, 7, S and 9) the bars are chargedthereon through doors located in side 18 of the chamber, (doors notshown) singly or in collection. standing either at the same or reversedinclination.

Before the commencement of a week or working period, and in order togain time,

the hearth is charged with its full comple-' ment of bars early enoughto bring them all to rolling temperature by the time the turn comes on.Following the withdrawal of the hot bars, at one end of the hearth, tobe rolled, others are charged to occupy reverse angular hot spaces inthe same grooves.

have been withdrawn. at which time the metal at the opposite ends of thechamber from which heated bars were last drawn is hot enough to roll;thus a rotative system of heating is established which continuesthroughout the Working period.

To recover heat in the hearth of Fig. 12, the bars are manipulatedsomewhatdiffer ently from those of Figs. 8 and 9', and the act isaccomplished by leaving the first groove 12, at the left of the figurevacant at the time the hearth is first charged with bars, which is afterthe hearth and all parts of the furnace have become'thoroughly heated.\Vhen such bars are partially heated, those occupying the first grooveat the right of the vacant groove 12 are turned over toward the leftinto said groove, this leaves the first previously occupied groovevacant and exposed to the normal temperature of the furnace which. itsoon assimilates; the next row of bars at the right of this re-heatedrooveis then turned toward the left into it, and as it is the hot topbar of the pair that comes in contact with the now re-heated'surface ofthe groove, such groove is robbed of but little heat. This operation iscontinued un-, til all of the barsv across'the hearth have been turnedinto temporarily vacated and This operation is continued until all ofthe bars extending over the hearthany. approved means.

re-heated grooves, at which, time, the first bars turned aresufiiciently hot to roll. After the hot bars occupying the first twogrooves 12. at the left end of the hearth have been drawn, cold bars arecharged into thesecond groove 12, which leaves the first groove againopen and prepared for a duplication of the operation, whichis constantlyrepeated.

In operating hearth 12, or any hearth of my invention herein describedwhere'the" bars are turned in process of heating, it ispreferableto heatand manipulate them' in pairs instead of greater collections.

The hearths shown in Figsfi, '7, 8, '9 and 12 are composed of burnedfire clay or any suitable refractory material and may be employed witheconomical results in the pair heating furnace of generaluse-where thereis but little sliding movement of bars'over the hearths surface,although the cast steel hearth nextbelow referred to is'preferred.

The hearth of Figs. 1, 2*, 3, 4, and 5 is the type preferably adopted inthe heating chamber of my' continuous heating furnace.

' It is by choice cast steel which is sufiiciently refractory towithstand the mild soaking heat required to mellow sheetbars and kindredmetal. The hearth extends out in the form of a shelf 17 (Fig. 1) beyondthe charging end 19 of said chamber a sufficient distance to upholdthereon sheet bars of the greatest length. Upon this shelf transverserows of the bars are placed singly or in collection, and in thelaterally inclined and lineal position they are to retain while passingalong the hearth which is in the longitudinal direction of thelrl'engthas indicated by 'the arrow, and preferably with their ends twice crossedin reverse angular abutment as shown in Figs. 2, 3, and 10, although, ifthe chamber be short, the rows of bars may be forced over the hearth,all

standing at the same angle and direction as shown in Figs. 8, 9 and 12.The shelf 17 being filled, the bars thereon are next forced within thechamber by an. hydraulic am or shelf is again refilled with similar rowsof bars which are also forced within the chamber. This operation iscontinued until the hearth is filled with bars its entire length. Thiscompleted, the bars are allowed to remain within the chamber until thetrans verse row at its discharge end 20 has reached the proper-rollingtemperature. The bars'of this row are then withdrawn and rolled. Aftersaid transverse row of bars has been exhausted and the shelf 17reloaded, the propelling mechanism is again applied to The thus emptiedthe exterior ends of the transverse rows of bars standing upon the shelf17, which forces them into .the chamber and-at the same time advances,the entire charge a dis-, v tance equal to the length of said row ofbars which occupied the shelf. This action brings a transverse row ofbars to the discharge end of the chamber properly heated and. inposition to be withdrawn the same as; said first row. 'This operation iscongatan'tly but intermittently repeated throughout'the week or workingperiod, The plan nace in advance of the first of heating bars in acontinuous heating furturn at the commencement of a working period is tobe barso'r other ,metal of-rectangular form in heating furnace,

: "various lengths of. any suitable within the heating chamber type ofheating furnace. Having described my invention, What I claim as new andfor which I desire to se-' cure Letters Patent, is

1. The herein described hearth ofa pair having its upper side composedof a series of parallel grooves suitable in form to uphold in angularposition, sheet bars placed longitudinally therein.

2. The herein described hearth of a pair heating furnace, having itsupperside composed of a series of parallel grooves suitable in form touphold in angular position, sheet bars placed longitudinally therein;the distance from the bottom of the grooves to their extreme outer barsupportingportions being greater than one-half the width of said bars.3. The herein described hearth of a pair heating furnace, having itsupper sidecolnposed of a series of parallel grooves which bear suchtransverse relation to each other that longitudinal rows of sheet bars,in sections, supported alternately at a reverse angle within the-groovesand against the sides thereof, will cross at their adjacent ends.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

THOMAS V. ALLIS.

Witnesses:

Enxsr FRANCKE, D. F. NISBET.

